bundles/org.simantics.browsing.ui.graph.impl/src/org/simantics/browsing/ui/graph/impl/contribution/CallbackViewpointContributionImpl.java

   1 /*******************************************************************************\r
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
   3  * in Industry THTH ry.\r
   4  * All rights reserved. This program and the accompanying materials\r
   5  * are made available under the terms of the Eclipse Public License v1.0\r
   6  * which accompanies this distribution, and is available at\r
   7  * http://www.eclipse.org/legal/epl-v10.html\r
   8  *\r
   9  * Contributors:\r
  10  *     VTT Technical Research Centre of Finland - initial API and implementation\r
  11  *******************************************************************************/\r
  12 package org.simantics.browsing.ui.graph.impl.contribution;\r
  13 \r
  14 import java.util.Collection;\r
  15 import java.util.function.Consumer;\r
  16 \r
  17 import org.simantics.browsing.ui.BuiltinKeys;\r
  18 import org.simantics.browsing.ui.BuiltinKeys.ViewpointContributionKey;\r
  19 import org.simantics.browsing.ui.DataSource;\r
  20 import org.simantics.browsing.ui.NodeContext;\r
  21 import org.simantics.browsing.ui.PrimitiveQueryUpdater;\r
  22 import org.simantics.browsing.ui.Tester;\r
  23 import org.simantics.browsing.ui.common.NodeContextUtil;\r
  24 import org.simantics.db.AsyncReadGraph;\r
  25 import org.simantics.db.ReadGraph;\r
  26 import org.simantics.db.common.request.ReadRequest;\r
  27 import org.simantics.db.exception.DatabaseException;\r
  28 import org.simantics.utils.ui.ErrorLogger;\r
  29 \r
  30 /**\r
  31  * Implement {@link #children(AsyncReadGraph)} and {@link #hasChildren(AsyncReadGraph)}.\r
  32  * \r
  33  * @author Tuukka Lehtonen\r
  34  */\r
  35 abstract public class CallbackViewpointContributionImpl extends ContributionStub {\r
  36 \r
  37     /**\r
  38      * @param graph\r
  39      * @param context\r
  40      * @return a collection of contributions, must not be <code>null</code>\r
  41      * @throws DatabaseException\r
  42      */\r
  43     abstract public void children(ReadGraph graph, NodeContext context, Consumer<Collection<?>> callback) throws DatabaseException;\r
  44 \r
  45     public CallbackViewpointContributionImpl(PrimitiveQueryUpdater updater,\r
  46             NodeContext context, ViewpointContributionKey key) {\r
  47 \r
  48         assert updater != null;\r
  49         assert context != null;\r
  50         assert key != null;\r
  51 \r
  52         this.updater = updater;\r
  53         this.context = context;\r
  54         this.key = key;\r
  55 \r
  56     }\r
  57 \r
  58     final protected PrimitiveQueryUpdater       updater;\r
  59     final private NodeContext                context;\r
  60     final private BuiltinKeys.ViewpointContributionKey    key;\r
  61 \r
  62     public NodeContext getContext() {\r
  63         return context;\r
  64     }\r
  65 \r
  66     @Override\r
  67     public Collection<NodeContext> getContribution() {\r
  68 \r
  69         //System.out.println("LazyViewpoint2@" + System.identityHashCode(this) + " getChildren() = " + children.length);\r
  70 \r
  71         if (children == org.simantics.browsing.ui.content.ViewpointContribution.PENDING_CONTRIBUTION) {\r
  72             DataSource<ReadGraph> source = updater.getDataSource(ReadGraph.class);\r
  73             if (source != null) {\r
  74                 source.schedule(graph -> {\r
  75                     ReadRequest childQuery = new ReadRequest() {\r
  76 \r
  77                         @Override\r
  78                         public void run(ReadGraph graph) throws DatabaseException {\r
  79                             try {\r
  80                                 children(graph, context,\r
  81                                         result -> replaceChildrenResult(NodeContextUtil.toContextCollectionWithInput(CallbackViewpointContributionImpl.this, result)));\r
  82                             } catch (DatabaseException e) {\r
  83                                 throw e;\r
  84                             } catch (Throwable t) {\r
  85                                 ErrorLogger.defaultLogError("LazyContributionImpl.childQuery produced unexpected exception.", t);\r
  86                             }\r
  87                         }\r
  88 \r
  89                         @Override\r
  90                         public String toString() {\r
  91                             return "LazyContributionImpl[" + System.identityHashCode(CallbackViewpointContributionImpl.this) + "].childQuery";\r
  92                         }\r
  93 \r
  94                     };\r
  95 \r
  96                     graph.asyncRequest(childQuery);\r
  97                 });\r
  98             }\r
  99         }\r
 100 \r
 101         //System.out.println("LazyViewpoint.getChildren returns " + children);\r
 102 \r
 103         return children;\r
 104 \r
 105     }\r
 106 \r
 107     protected void replaceChildrenResult(Collection<NodeContext> result) {\r
 108         setChildren(updater, result);\r
 109         updater.scheduleReplace(context, key, this);\r
 110     }\r
 111 \r
 112     /**\r
 113      * @param <T>\r
 114      * @param clazz\r
 115      * @return input of the specified class\r
 116      * @throws ClassCastException if the input class does not match the\r
 117      *         specified class\r
 118      * @throws NullPointerException if the input is null\r
 119      */\r
 120     @SuppressWarnings("unchecked")\r
 121     protected <T> T getInput(Class<T> clazz) throws ClassCastException {\r
 122         Object o = context.getConstant(BuiltinKeys.INPUT);\r
 123         if (o == null)\r
 124             throw new NullPointerException("null input");\r
 125 //        return clazz.cast(o);\r
 126         return (T) o;\r
 127     }\r
 128 \r
 129     /**\r
 130      * @param <T>\r
 131      * @param clazz\r
 132      * @return <code>null</code> if input is <code>null</code> or if the class does not match\r
 133      */\r
 134     @SuppressWarnings("unchecked")\r
 135     protected <T> T tryGetInput(Class<T> clazz) {\r
 136         Object o = context.getConstant(BuiltinKeys.INPUT);\r
 137         if (o != null && clazz.isInstance(o))\r
 138 //            return clazz.cast(o);\r
 139             return (T) o;\r
 140         return null;\r
 141     }\r
 142 \r
 143     @Override\r
 144     public Tester getNodeContextTester() {\r
 145         return null;\r
 146     }\r
 147 \r
 148 }\r